In any stereo system, there are a variety of means available to increase listening pleasure. The more common of these include utilization of high quality recording media (e.g., compact disc rather than cassette tape) and control of the characteristics of the signal sent to the loudspeakers (e.g., attenuation or gain of the signal at various frequencies and control of the relative signal strength between the different speakers in the system).
With respect to a given loudspeaker, the most that can typically be done to increase listening pleasure is to orient the speaker either by itself or in relation to other speakers. However, the positions of automobile loudspeakers are typically fixed within the automobile, whether they are mounted in the door panel, the front or rear window ledge, or otherwise. The automobile occupants are therefore captive to the particular speaker arrangement provided by the automobile manufacturer. Moreover, automobile window ledge speakers are conventionally mounted flush with the surface of the window ledge. While this arrangement permits the loudspeaker to be virtually hidden, minimizing its impact on the aesthetic look of the automobile interior, it results in the sound emanating from the speaker being directed upwards rather than toward the automobile occupants.
To better direct the loudspeaker output toward the occupants, rear window ledge speakers have been mounted on top of the rear window ledge such that the speaker faces forward toward the occupants. See, for example, U.S. Pat. No. 4,630,303, issued Dec. 16, 1986 to T. Tanno, which discloses an automobile speaker system that is located upon the rear window ledge and which includes a high range speaker that is designed to extend upwardly and slant forwardly to avoid attenuation of high range sounds due to the interposition of a rear seat, backrest, or head rest between the high range unit and the listener. Although suitable for its intended purpose, the arrangement disclosed in that patent suffers from several disadvantages. Firstly, control over positioning of the speaker is limited. The position of the low range unit cannot be changed and orientation of the high range unit is limited to elevational changes. Secondly, the presence of the speakers is highly conspicuous, which for many automobile interior designs is undesirable. Thirdly, the system cannot be implemented with a single speaker, nor can it be implemented with coaxial or triaxial speakers commonly used in automotive applications, as the high and low range speakers must be physically separate components that are movable with respect to each other.